The present invention incorporates synthetic resin thermoplastic panels or pieces, such as baseboard-type panels, that are joined by an integral hinge and that include resilient injection molded portions. The hinged panel or piece of the present invention may be used in a variety of applications such as to provide sealing ends on or between hinged thermoplastic panels or to create resiliently closeable passages in or between hinged thermoplastic panels through which wires and other objects may be passed while maintaining an even surface appearance of the baseboard panel.
The present invention pertains generally to the field of thermoplastic constructions such as those in office furnishings and equipment, hospital and clinic furnishings, cafeteria furnishings, office partitions, etc.
Office furnishings and equipment, and the like, are often put into service in environments where there is exposure to impact and abrasion, such as through heavy foot traffic, hand contact, or exposure to things in motion, such as office equipment, dollies, carts, tables, chairs, wheelchairs, and hospital beds.
Office furnishings and equipment, and the like, are typically provided with baseboards, railings, and other pieces to resist or absorb impacts and scuffing, as well as to present and maintain an even and neat appearance in the presence of such wear and tear.
It is also often the case that such furnishings incorporate trim pieces, and the like, to provide a continuous covering or finish. However, such pieces must be produced so as to be securely incorporated into the balance of the furnishing piece, such as along the top or bottom of office partitions. Accordingly, it is desirable to be able to produce a thermoplastic piece or panel capable of secure incorporation into a top or bottom raceway or conduit of a furnishing piece such as a wall-type divider or partition panel.
It is also preferred in many applications for plastic or synthetic resin articles to have inherent flexibility in certain localized areas, without introducing irreversible distortion or fracture of the plastic during flexing. More specifically, many applications require portions of the synthetic resin article to be substantially rigid to provide structural integrity during its intended use. However, for ease of installation certain portions of the article should be relatively flexible, but not so soft as to affect the overall utility of the article for its intended use. Thus, the need arises for synthetic resin articles having a relatively flexible semi-rigid area connecting substantially more rigid areas, approximately analogous to a hinge. Such hinges in synthetic resin articles are used in numerous applications. A few illustrative examples are explicated to clarify, in a practical sense, the utility of such synthetic resin thermoplastic hinges.
Folding doors are often constructed of numerous rigid plastic panels joined by relatively flexible plastic hinges. The plastic joining material must be sufficiently flexible to permit the individual door panels to fold or collapse to nearly a face-to-face parallel geometry when the folding door is fully open (contracted). Yet the same flexible plastic joining material must be sufficiently durable to withstand many flexing operations, and to form an integral part of the door itself when the door is fully closed (extended). Thus, the plastic joining material must have a correct balance of flexibility, without being too soft, to function as an integral part of the closed door.
A major use for semi-rigid synthetic resin thermoplastics is for office construction and furnishing applications. For example, in office furnishing systems, a semi-rigid plastic is a very convenient way to join space separation panels at a variety of angles for a variety of office configurations, without incurring unacceptable expense in assembly and disassembly.
A further application to such office furnishings involves hinged access panels, such as baseboard-type panels, to enable easy access to office equipment, electrical cabinets, etc. Flexibility is clearly required for a hinge on a multi-sectioned access panel, but certain rigidity and structural integrity is also desirable.
As a final illustrative example, for raceway covers and baseboard panels as used in office furnishing systems it is desirable to have hinge-type flexibility while retaining rigidity and durability properties of sections of the hinged thermoplastic synthetic resin panels. Rigidity is required of the panels or pieces to maintain a structurally sound covering, while some flexibility at the hinges is needed for rapid installation in a variety of geometries of home, office, and industrial furnishing panels, dividers, and/or partitions.
These examples illustrate a few of the cases in which hinge areas in thermoplastic panels or pieces are desirable. One common method for constructing such hinges is to coextrude the rigid plastic material to have an integral score line extruded into the panel or piece that forms a hinge line in the direction of extrusion, along the line about which the final product is required to flex.
The hinged thermoplastic panel or piece of the present invention also preferably incorporates a resilient plastic portion that is configured to form sealing ends on or between a plurality of hinged thermoplastic panels or to create resiliently closeable passages in or between the hinged thermoplastic panels through which wires and other objects may be passed while maintaining an even surface appearance of the baseboard panel.
To achieve this end, it is often desirable to be able to take advantage of two or more plastic materials having different flexion and appearance qualities by incorporating them into a single part. This is complicated by the fact that attempts to incorporate different materials require a secondary adhesion operation. This secondary operation often involves specialized adhesives or the injection molding of different polymers under adverse conditions. Such adverse conditions: (1) may not allow the two materials to sufficiently adhere, or (2) may mar the surface or other aesthetic qualities of the part, or both (such as through the application of heat or pressure, or both). To address these and other problems, the present invention provides a method of integrating dissimilar synthetic resin polymers to one another.
It is also often desirable to be able to produce plastic composites capable of being used as sight and/or light barriers, as well as to produce products that present and maintain desirable aesthetic qualities such as those needed on office furnishings like room divider or partition panel raceway covers.
Also, in many instances, these pieces must be made to allow the passage of various electrical and signal transmission wires, fiber optic cables, and the like, which are often necessary to operate office equipment such as, for example, telephones, computers, copiers, printers, projectors, networks, lights, and electrical outlets.
To this end, office furnishing divider or partition panels normally have been provided with holes or gaps along a top, middle, or bottom portion to allow wires and cables to be passed through regions therein commonly referred to as raceways. However, the various potential applications of thermoplastic hinged baseboard panels, their arrangement, and their working environments make it difficult to predict where wire/cable access will be needed, and the size and number of wires or cables to be passed through at a given location.
One of the ways of constructing a thermoplastic baseboard hinge panel to have gaps therein or panels that form gaps between one or more of such panels, is to extrude a relatively rigid panel of material such as a rigid PVC. These panels are then cut to a desired length and a relatively flexible polymeric material, such as a flexible PVC material, is then adhered to the relatively rigid material through use of an adhesive, such as a cyanoacrylate adhesive, in a secondary hand operation.
There are several problems attendant to the use of such adhesives in hand operations. One problem is that of ventilation. The adhered pieces must normally be carefully stacked to provide sufficient curing and ventilation. Also, in the case of cyanoacrylate adhesives, the vapor issuing from the curing adhesive can form a white deposit on the finished pieces, often rendering them unacceptable to the manufacturing customer. Naturally, any gaseous emissions from curing adhesive may pose a health hazard to the operator.
The use of liquid adhesives in hand operations are also inefficient. Liquid adhesive can be spilled, requiring cleanup, and hand operations, even when carefully done, can lead to gaps in the alignment between the rigid and flexible portions. It is therefore more difficult to manufacture such pieces within required tolerances.
Finally, the use of liquid in hand operations must rely upon the operator to dispense the appropriate amount of adhesive uniformly to be sure that a strong bond is achieved. This is often difficult to do efficiently in repetitive, mass-production operations.
Accordingly, it is desirable to be able to produce a thermoplastic hinged baseboard panel that can accommodate, alternatively, the throughput of a small or great number of wires (or wires of a small or great diameter) or remain unused, while maintaining an even, aesthetically acceptable appearance and without the use of separable parts.
It is also desirable to be able to produce such a furnishing panel in a continuous process without the need for secondary, post-extrusion operations (that is, a piece or panel that can be produced in a continuous in-line process).
The present invention also produces a furnishing panel with a strong and uniform bond across the interface between the rigid and flexible sealing or resilient portions, while eliminating the environmental hazards, inefficiencies, and production objections discussed above.
Also, the present invention provides an aperture covering for a piece or panel which is durable and resists the impact and flexion often occurring in high traffic home, office, industrial environments, and the like.
In view of the present disclosure and/or through practice of the present invention, other advantages and the solutions to other problems may become apparent.
One embodiment of the present invention is directed to a panel for a furnishing piece that includes a thermoplastic piece that is adapted to be attached to the furnishing piece. The thermoplastic piece is formed with a plurality of outer cover sections connected by a center spine. The spine and the outer cover sections include inner and outer surfaces and a lateral terminal edge. The thermoplastic piece also includes an extension portion made from a thermoplastic material that is relatively more flexible than the thermoplastic piece. The extension portion is injection molded onto the respective the inner surfaces of the thermoplastic piece so as to extend beyond at least one of the respective the lateral terminal edges. In a variation of this embodiment, the center spine also incorporates a registration guide adapted to improve the precision of the location of the extension portion relative to the thermoplastic piece.
The thermoplastic piece is preferably fabricated from a material selected from the group consisting of rigid polyvinylchloride (xe2x80x9cPVCxe2x80x9d) having a Shore D scale hardness of at least 75 according to the American Society for Testing and Materials (xe2x80x9cASTMxe2x80x9d) testing method D-785. Alternatively, the thermoplastic piece can be made from a material selected from the group consisting of rigid PVC having a Shore D hardness in the range of from about 50 to about 90 according to ASTM method D-785. More preferably, the thermoplastic piece can be made from a material selected from the group consisting of rigid PVC having a Shore D hardness in the range of from about 78 to about 82 according to ASTM method D-785.
In additional variations of this embodiment, the extension portion is selected from the group consisting of ethyl vinyl acetates, urethanes, thermoplastic urethanes, PVC-urethane alloys, alloyed vinyls, thermoplastic rubbers, polyester elastomers, and polytetramethylene glycol esters. More preferably, the extension portion is selected from the group consisting of ethyl vinyl acetates and urethanes having a Shore A hardness in the range of from about 60 to about 95 according to ASTM method D-2240.
The present invention is also directed to a partition panel that includes an elongated baseboard formed from a first polymeric extrudate having a lateral leading edge with inside and outside surfaces and further formed with longitudinal hinge portions connecting a center spine to outer sections. The elongated baseboard further includes a plurality of resilient extension members formed from a second polymeric extrudate having an attachment portion thermally welded proximate to the leading edge to the respective inside surfaces of the outer sections, the attachment portion being separated by a step-down from an exterior portion formed with an outside surface adapted to be substantially flush and coplanar with the respective outside surfaces of the baseboard. The second polymeric extrudate is preferably more flexible than the first polymeric extrudate. A variation of this embodiment includes a center spine of the first polymeric extrudate that further incorporates a registration guide adapted to improve the precision of the location of the extension members relative to the first polymeric extrudate.
In a variation of this embodiment, a workplace partition incorporates an elongated baseboard formed from a first polymeric material that has leading and trailing ends and therebetween a center spine having longitudinal hinge portions connected to outer cover sections each having opposite inner and outer faces. The elongated baseboard also includes resilient first and second extension pieces injection formed from a second polymeric material and molded proximate to the respective leading and trailing edges and onto the respective inner faces of the respective outer cover sections. Each extension piece includes a fascia portion extending outwardly from the leading and trailing edges, respectively. The fascia portions are generally coplanar with the outer faces and the first polymeric material is relatively less flexible than the second polymeric material. A further variation includes a center spine of the elongated baseboard that further incorporates a registration guide adapted to improve the precision of the location of the extension pieces relative to the respective leading and trailing edges.
The present invention further contemplates a partition baseboard assembly that includes a plurality of elongated polymeric extrudate baseboards formed with inside and outside faces and leading and trailing edges. Each baseboard includes a center spine with integrally hinged outer cover sections. Incorporated in the elongated baseboards are a plurality of flexible extension pieces formed from a polymeric material more resilient than the polymeric extrudate and thermally molded onto each respective inside face and proximate to the leading and trailing edges, respectively. The flexible extension pieces extend from the leading and trailing edges, respectively, so that, when a pair of the plurality of baseboards are positioned with a leading edge proximate to a trailing edge to form a gap therebetween, a pair of the plurality of flexible extension pieces resiliently covers the gap. A modification of this embodiment includes a registration guide formed in the center spine that is adapted to improve the precision of the location of the extension pieces relative to the respective leading and trailing edges. In a further variation, the pair of flexible extension pieces overlaps one another to resiliently seal the gap.
In yet another variation of the present invention, a polymeric extrudate member is described that includes a thermoplastic piece formed with a plurality of outer cover sections hingeably connected by a center spine, with the spine and each section including an inner and an outer surface, respectively. A gap surrounded by at least one peripheral edge is formed in each outer cover section and cooperatively positioned to establish a passageway when the outer cover sections are folded into an installed position about a furnishing piece. A plurality of extension pieces of a thermoplastic material, that are relatively more flexible than the thermoplastic piece, are injection molded onto the respective inner surfaces of the thermoplastic piece proximate to the at least one peripheral edge so as to extend about a portion of each of the gaps to resiliently and closeably seal the passageway. As with previous variations, the center spine of the elongated baseboard may also further incorporate a registration guide adapted to improve the precision of the location of the extension pieces relative to the passageway.
The present invention is also directed to a method for applying a thermoplastic polymeric portion to the surfaces at either end of a series of thermoplastic extrudate members each having leading and trailing edges, inside and outside surfaces proximate thereto, and a center spine hingeably connected to opposite outside cover sections. The method includes the steps of: (a) aligning a first thermoplastic extrudate member so as to position its leading edge in an injection mold cavity; (b) injection molding a plurality of thermoplastic polymeric portions onto a respective plurality of inside surfaces of the first thermoplastic extrudate member proximate to its leading edge; (c) transporting and aligning the first thermoplastic extrudate member so as to position its trailing edge in the injection mold cavity, and transporting aligning a second thermoplastic extrudate member so as to position its leading edge in the injection mold cavity; (d) injection molding substantially simultaneously (1) a plurality of thermoplastic polymeric portions onto the respective inside surfaces of the first thermoplastic extrudate member adjacent its trailing edge, and (2) a plurality of thermoplastic polymeric portions onto the surface of the second thermoplastic extrudate member adjacent its leading edge; (e) transporting the first thermoplastic extrudate member from the injection mold cavity, transporting and aligning the second thermoplastic extrudate member so as to position its trailing edge in the injection mold cavity, and transporting and aligning a third thermoplastic extrudate member so as to position its leading edge in the injection mold cavity; and (f) repeating steps (c) through (e) for fabricating successive thermoplastic extrudate members beyond the third thermoplastic extrudate member.
In this method, the center spine of the thermoplastic extrudate members may further include a registration guide. Also, the transporting and aligning steps may further include the step of registering the registration guide in the mold cavity to improve the alignment of the thermoplastic extension portions relative to the respective leading and trailing edges.
A variation of this method includes producing a plurality of polymeric extrudate members each having a center spine hingeably connected to opposite outside cover sections by employing the steps of: (a) aligning: (i) a first thermoplastic member of the plurality having a substantially flat first inside surface proximate to a first trailing edge; and (ii) a second thermoplastic member of the plurality having a substantially flat second inside surface proximate to a first leading edge and a second trailing edge; whereby the first trailing edge and the first leading edge are side by side in a molding relationship with an injection molding cavity; (b) injection molding a plurality of flexible thermoplastic members onto, respectively: (i) the first inside surface to extend outwardly from the first trailing edge, and (ii) the second inside surface to extend outwardly from the second leading edge; wherein the flexible thermoplastic members are relatively more flexible than the first and second thermoplastic members; (c) advancing the first and second members so as to align: (i) the second trailing edge of the second thermoplastic member of a polyvinylchloride material; and (ii) a third thermoplastic member of the plurality having a substantially flat third inside surface proximate to a second leading edge and a third trailing edge; whereby the second trailing edge and the second leading edge are side by side in a molding relationship with the injection molding cavity; (d) injection molding a plurality of flexible thermoplastic members onto, respectively: (i) the second inside surface to extend outwardly from the second trailing edge, and (ii) the third inside surface to extend outwardly from the third leading edge; wherein the flexible thermoplastic members are relatively more flexible than the second and third thermoplastic members; and (e) repeating steps (c) and (d) to fabricate fourth, fifth, and successive polymeric extrudate members of the plurality. In a variation of this method, each of the polymeric extrudate members of the plurality further incorporates a center spine having an integral registration guide adapted to improve the precision relative position of the extrudate members during the aligning and advancing steps. The method also contemplates polymeric extrudate members of the plurality that are fabricated from PVC and flexible members that are fabricated from a urethane material.